Crawling through Zip files - vba

Question

I'm trying to crawl through a certain drive and grab data off of certain .xls files that are buried in sub-directories. The drive is over a TB, and the folders don't all have the same hierarchy, so I'm crawling through all of them. So far, the script works great.
The problem is, there are zipped files in the drive. At least half the files are in zipped format. How can I crawl through these files as well?
Here is the part of my code that crawls through the sub-directories. There is another function "TrailingSlash" which just appends a "\" to the string if it doesn't already have one. I give credit to the author in my comments.
Public Function recursiveDir(colFiles As Collection, strFolder As String, strFileSpec As String, bIncludeSubfolders As Boolean) as Collection
'From Ammara.com/access_image_faq/recursive_folder_search.html
'Recursive function to search document tree from specific file extension
Dim strTemp As String
Dim colFolders As New Collection
Dim vFolderName As Variant
Dim colFiles As New Collection
Dim counter As Integer
'Add files in strFolder matching strFileSpec to colFiles
strFolder = TrailingSlash(strFolder)
strTemp = Dir(strFolder & strFileSpec)
On Error Resume Next
Do While strTemp <> vbNullString
colFiles.Add (strFolder & strTemp)
counter = counter + 1
Debug.Print ("files found: " & counter)
strTemp = Dir
Loop
If bIncludeSubfolders Then
'Fill colFolders with list of subdirectories of strFolder
strTemp = Dir(strFolder, vbDirectory)
Do While strTemp <> vbNullString
If (strTemp <> ".") And (strTemp <> "..") Then
If (GetAttr(strFolder & strTemp) And vbDirectory) <> 0 Then
colFolders.Add strTemp
End If
End If
strTemp = Dir
Loop
'Call recursiveDir for each subfolder in colFolders
For Each vFolderName In colFolders
Call recursiveDir(colFiles, strFolder & vFolderName, strFileSpec, True)
Next vFolderName
End If
recursiveDir = colFiles
End Function
The function adds all the path strings to the collection "colFolders", which I then use to open and extract data from. I'm now thinking there may not be a simple way to return a string path to a file within a zipped folder. There may need to be a separate function that is called when this function encounters a zip, that in turn crawls through the zipped folder and extracts the specific file to a local destination (as long as I don't have to extract the whole folder, we should be good).
I'm kind of lost in what I should do. Googleing around points me towards using shell.Application. I know nothing of shells, is this the path I should take?
Thanks SO - you all are awesome!

Answer 1

Try this code instead to search through subfolders:
Sub SO()
Dim x, i
x = GetFiles("C:\Users\SO\Folder", "*.xls*", True) '// x becomes an array of files found
For Each i In x
Debug.Print i
Next i
End Sub
'-------------------------------------------------
Function GetFiles(StartPath As String, FileType As String, SubFolders As Boolean) As Variant
StartPath = StartPath & IIf(Right(StartPath, 1) = "\", vbNullString, "\") 'Sanity check
GetFiles = Split(Join(Filter(Split(CreateObject("WScript.Shell").Exec("CMD /C DIR """ & StartPath & FileType & """ " & _
IIf(SubFolders, "/S", vbNullString) & " /B /A:-D").StdOut.ReadAll, vbCrLf), ":"), "#"), "#")
End Function
But for zip files, there isn't really anything native to windows that will allow you to do this other than the CreateObject("Shell.Application").Namespace(zipName).Items method.
I prefer to use 7-zip which is free, open-source and has a great command line utility which means you can access it via VBA too using the CreateObject("WScript.Shell") method (like above)